The "Submarine Jeep" started out life as a 1946 CJ2A, and the original family installed an M151A2 powerpack in during the 1970's. I purchased this from a good buddy who I've sold Jeeps to as well. We're both restoring each other's projects, which is neat. I've spent significant time deciding on a route for this project. Initially I was going to slap some paint on and wheel it. It has quickly turned into a total refurbish which I'm going to finish by the end of summer - to go wheeling with my college buddies. I do plan on submerging the Jeep! Why else own a Mutt drivetrain?

Current progress: Have drive the Jeep around the block, but the transmission most likely needs rebuilt (as it doesn't shift into 1st or 2nd). Somehow I picked up a powerpack for $200 with the 24V generator. My plan is to swamp transmissions and install the coveted generator. The current Jeep frame is bent from years of plowing in Colorado. I'm picking up a sandblasted and primed frame shortly. There's been some major body repairs, also turning it into a fake MB. Most my progress has been accumulating information and parts so I can work quickly during the summer.

16'' flex front18'' flex rear

Body repairs

Hydraulic clutch?

2nd powerpack

Questions:1. Where should I send this generator to be refurbished?2. I'm considering buying a factory Mutt exhaust snorkel. I like the size and the cage around it. My plan is to cutt it down to fit the roll bar. Since it would be my only muffler, how quiet are they?3. Are there smaller batteries I can use to run the engine? My engine bay is limited.

There is no muffler in the snorkel, it is just a straight piece of pipe. The stock muffler is just a straight through setup as it is so the stock setup with the snorkel is not all that quiet. If you are not running any muffler at all it will be loud and raspy. Also kind of expensive considering it is designed to fit a mutt and will have to be heavily modified to fit your application. Might as well have a shop build one from scratch.

Is the transmission going to tuck up in there with room for the e-brake drum? Floor looks good and clean but if you are planning on submerging this a lot I would think it would have a a lot more drainage.

rickf wrote:Is the transmission going to tuck up in there with room for the e-brake drum? Floor looks good and clean but if you are planning on submerging this a lot I would think it would have a a lot more drainage.

I was smart enough to mock up the main dimensions of the cover before removing the tub.

As for the drainage: The front section of the floor was patched. At the area where the floor steps up, there's a few 10" long slots where I didn't weld them together.

Where does the go-pedal go? Things look kinda crowded in the driver's footwell.

Out of curiosity, was this swap solely for the purpose of doing submersible stuff or because this was just an extra power pack you had laying around?

Are you going to reseal your power pack and driveline before going in the water? This is something you should give very serious consideration to. Older seals may still do a good job of holding oil and grease in but those things aren't under the kind of pressure that water presents. Take it from an old SCUBA diver...water under pressure is chiefly the problem that submergence presents. There is a very good chance that water will be migrating into your truck's working parts past older seals.

Fording kit, It pressurizes the innards so no water gets in. The engine anyway. You could make a system from a small compressor to do the trans and diffs under the same principal. You only need a 1/2 il. of pressure at the most injected through the vent fitting. Valved to atmosphere normally.

Where does the go-pedal go? Things look kinda crowded in the driver's footwell.

Out of curiosity, was this swap solely for the purpose of doing submersible stuff or because this was just an extra power pack you had laying around?

Are you going to reseal your power pack and driveline before going in the water? This is something you should give very serious consideration to. Older seals may still do a good job of holding oil and grease in but those things aren't under the kind of pressure that water presents. Take it from an old SCUBA diver...water under pressure is chiefly the problem that submergence presents. There is a very good chance that water will be migrating into your truck's working parts past older seals.

Cheers,TJ

Thanks for the interest. The gas pedal is mounted just below the brake pedal. I sat for hours trying to figure where to place everything, but between the limited space and roll cage I was stumped. It might turn out to be a superior system for heel-toe downshifting.

My buddy purchased this Jeep from the original family that built it. The story goes a Vietnam vet built this in the 70s because the Willys L-head just wasn't fast enough. I feel in love with the idea of water fording capabilities. In retrospect I should have built a Jeep from scratch as I'm redoing just about everything the original guy did. His ideas were ambitious... but execution another story.

As she sits:I discovered the original frame was severely bent and rust taking over structural integrity. So I restored a donor 3A frame.

Restored the tub and placed it on the new frame. I'm within 1/16" accuracy in comparison of my all-original CJ3A.

Fitting the drivetrain perfectly within my custom tranny tunnel was grueling. If Novak offered a kit I would absolutely spent hundreds for it.

Next I fit the accessories such as radiator and M38A1 air cleaner. It's very, very cramped in there. I'm going to run an electric fan setup for the water. Space is so tight I actually cut off the 1/2" nipple on the water pump for clearance. It's odd - I had room for the mechanical fan when the radiator was mounted on the power pack on the old Jeep, but this setup there is no room. The engine actually sits closer to the firewall and the radiator is hard mounted on the frame.

13,000 lbs. winches will be on the front and rear. I spent weeks designing the perfect rock sliders and roll cage. At the moment the rear half of my cage needs finished.

All in all, I'm very impressed with the build. I'm very picky with modified vehicles, but the submarine has surpassed my expectations and is becoming a tasteful "super stock" Jeep. I'm already considering it one of my favorite flat fender builds alongside Bam Bam and Rango.

Looks good. I know I have mentioned a couple times in our phone conversations that I think you are nuts for building this with a transmission with no low range but I have to admire the dedication and amount or detail you are putting into this project. I am anxious to see it in action.

I want to point out something here because you have asked several times about different items, like the starter and alternator, it they are "waterproof". Waterproof, by definition, means no water will get in at all. That is not going to happen with any of these items due to the fact that they get hot and they have rotating parts. If you have a starter bolted t the engine it is going to get pretty hot. Now, dunk that starter underwater and it is going to cool off in a big hurry and form a vacuum inside from the air contracting in there, The seals are going to let water in. They are mainly dust seals and on top of that they will only work in one direction. Now you have water in there it has to get out, if it is waterproof then the water can't get out. Same with the alternator, if it were waterproof there is cooling which you have to have. The clutch, they tell you to put the plug in before fording, I would bet anything that as soon as you put that hot transmission under water it will just suck right through the clutch rod boot! Now the bell housing is FULL of water and the plug is in until you can get to a place to take it out. What has been accomplished? Nothing. If the plug was left out the water would get in and run right back out. For years I ran my Jeeps and old Broncos under water with all the stock parts, clutch, alternators, starters. They did not fail any faster than any other parts. The clutches lasted longer I think because all the garbage was rinsed out regularly.

rickf wrote:Looks good. I know I have mentioned a couple times in our phone conversations that I think you are nuts for building this with a transmission with no low range but I have to admire the dedication and amount or detail you are putting into this project. I am anxious to see it in action.

I want to point out something here because you have asked several times about different items, like the starter and alternator, it they are "waterproof". Waterproof, by definition, means no water will get in at all. That is not going to happen with any of these items due to the fact that they get hot and they have rotating parts. If you have a starter bolted t the engine it is going to get pretty hot. Now, dunk that starter underwater and it is going to cool off in a big hurry and form a vacuum inside from the air contracting in there, The seals are going to let water in. They are mainly dust seals and on top of that they will only work in one direction. Now you have water in there it has to get out, if it is waterproof then the water can't get out. Same with the alternator, if it were waterproof there is cooling which you have to have. The clutch, they tell you to put the plug in before fording, I would bet anything that as soon as you put that hot transmission under water it will just suck right through the clutch rod boot! Now the bell housing is FULL of water and the plug is in until you can get to a place to take it out. What has been accomplished? Nothing. If the plug was left out the water would get in and run right back out. For years I ran my Jeeps and old Broncos under water with all the stock parts, clutch, alternators, starters. They did not fail any faster than any other parts. The clutches lasted longer I think because all the garbage was rinsed out regularly.

Hey Rick always good to see your posts. I try not to think about the lack of low range for the sake of my sanity. On the good side I'm running a lower axle ratio and smaller tire than the M151. And... this guys went nuts and built an entire rock buggy with the power pack! http://www.g838.org/viewtopic.php?p=48379#p48379

As you know I have done extensive research. I've found out that the old school parts were simply built better than the junk we get today. I ripped through 1 foot of water on my Wrangler JK and destroyed the alternator. My buddy has gone through several as well. Newer alternators just can't handle water.

Great to know about the vacuum sucking in water - I haven't thought about that. I've checked out the bellhousing and there is no way it'll be completely sealed. I'm going to pull the plug and just run it. The 12V conversion has also raised huge questions on waterproof parts. I contacted RAPCO in Texas and they are getting in a shipment of 12V starters. They have no idea if it'll be a day, month, year... or if it will cost $10, $10,000. If anyone has a 12V starter I would be very interested. On the generator: I decided the Humvee 24/12V setup was ridiculous and too heavy (70 lbs.). So I'm going to have my 60 amp one rebuilt. Maybe with this kit?http://www.ebay.com/itm/M151-M151A2-MUTT-24v-24-volt-Generator-Overhaul-Rebuild-Kit-G838-/172822957105?hash=item283d0d0c31:g:lWcAAOSwrFJZyDzR&vxp=mtr

From the generator outputting 24V, I will have a marine converter to 12V. This means I can keep the stock mounting brackets, have access to parts, and be waterproof. It seems only the M-series generators are waterproof and there isn't an alternative.

I have also debated hooking up a small air compressor as you suggested earlier. At the moment it is only setup where I run vent lines to the air cleaner and snorkel. Including the master cylinder, axles, fuel cell, and the tranny if there is a vent. However under the pressure of water, I'm not sure if that will be enough? My goal is to not replace parts every time I dunk this thing in the pond. It needs to be as reliable as possible. With minimal maintenance. And I believe built right... it can be done.

Keep in mind that the military required a full maintenance as soon as possible after fording because they knew there would be water in the differentials and everywhere else it shouldn't be. I ran high vents on my jeeps (still do) but the diffs still get water in them. The vent will prevent a vacuum from forming and pulling in water but water pressure against a seal that is designed to keep oil in will let water push right past. The only solution would be a seal with lips facing both directions, or double up the seals in a specially machined area of the axle housing. Then the problem is how to keep the outer seal lubricated so it doesn't burn up. I'll tell where to look for information and that is the SEEP. The military amphibious Jeep from WWII. They supposedly kept the water out of those axles as it swam across lake and rivers. And they were Dana axles. See what kind of seals they used in them. I don't know the first thing about them so I can't help there.

Ok guys I'm at a dilemma in the build and have a question about the charging system. The only 24V part on this Jeep is the coil and 60 amp alternator. This is because I can't find a single waterproof 12V alternator. It seems to be impossible. Only the military is crazy enough to build this stuff, and they use 24V.

So I have 24V alternator --> 24V to 12V reducer --> battery. The reducer has an internal voltage regulator. So does the Mutt alternator, and the field wire will be looking for a 24V reading to tell itself how much voltage to output. This is unnecessary as (a) I have a 12V battery and (b) the reducer will be the one regulating. Is there a way to bypass this system? Trick the alternator into reading properly for 12V?

Nick, It is looking real good. I still think you are overthinking this but hey, I am an old fart so go for it. I am putting the contact info for George, one of our premier members below. George is in Holland and has extensive electrical knowlege and has come up with solutions to all kinds of weird problems. Many of them involving voltage conversions. Brush up on your Dutch, he types with an accent. Seriously, I bet he will have a solution. He may have a completely different way of routing things, pay attention to what he says, he does this for a living.